Invertebrates inspire fear or disgust in many people for various reasons, including their appearance and the often unfamiliar crawly sensation that accompanies the touch of legs and feelers against the skin. Most are actually harmless to man and in many cases they play a much larger role in an ecosystem than other animals. As a result, invertebrates have often been used as monsters in myth and legend, such as the Kraken, based on the giant squid, and Arachne from Greek mythology.

Arthropods (from the Greek árthron, meaning joint, and podos, meaning leg or foot), are the most diverse phylum of invertebrates, consisting of an estimated 80% or so of all animal species. They contain the insects, arachnids, crustaceans, myriapods (millipedes and centipedes), and others.

Arthropods are known for their hard exoskeletons comprised of chitin and often reinforced with calcium carbonate, distinct body segments, distinct limb jointing and six or more limbs (with all insects having exactly six limbs).

While some will prefer to make invertebrate anthros with full features such as exoskeleton, antennae, multiple limbs and abdomen, most make use of a minimal set of features - typically only antennae, wings (when present in the actual species) and body patterns, with exception of spiders, which are usually portrayed with six legs plus body patterns. Another known concept is the one of a drider, a D&D-based concept which consists of a taur form with the lower body being of a spider.

Most anthropomorphic invertebrate characters tend to be arthropods, perhaps because of their ubiquitous presence across the world. In particular, invertebrate characters tend to be insects or arachnids.

The level of anthropomorphism tends to vary considerably, for example between retaining the limb number, a full exoskeleton, compound eyes, wings, mandibles, etc., with considerable differences between characters; for example, a character with a more humanoid looking exoskeleton might have mandibles, whereas another might have a more insectoid exoskeleton but a humanoid mouth, and so on.

The inhabitants of Cyeatea in the NSFW webcomics Dreamwalk Journal and Nightshade the Merry Widow are anthropomorphic hybrids of various insect and spider species, typically possessing human-like eyes, upper torsos, arms and genitalia.